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William Thordarson

Publications and source records attributed to William Thordarson.

At least 19 recordsLinked to original sources
USGS1985

Geohydrology of test well USW H-3, Yucca Mountain, Nye County, Nevada

Test well USW H-3 is one of several wells drilled in the southwestern part of the Nevada Test Site for hydraulic testing, hydrologic monitoring, and geophysical logging. The work was performed in cooperation with the U.S. Department of Energy. The rocks penetrated by the well to a total depth of 1,219 meters were volcanic tuffs of Tertiary age. The most transmissive zone in this well is in the upper part of the Tram Member of the Crater Flat Tuff that was penetrated at a depth from 809 to 841 meters; transmissivity is about 7 x 10 -1 meter squared per day. The remainder of the rocks penetrated between the depths of 841 to 1,219 meters have a transmissivity of about 4 x 10 -1 meter squared per day and are predominatly in the Tram Member of the Crater Flat Tuff and the Lithic Ridge Tuff in the depths from 841 to 1,219 meters. (USGS)

Water-Resources Investigations Report↗
USGS1985

Geohydrology of rocks penetrated by test well USW H-4, Yucca Mountain, Nye County, Nevada

Test well USW H-4 is one of several wells drilled in the southwestern part of the Nevada Test Site for hydraulic testing, hydrologic monitoring, and geophysical logging. The work was performed in cooperation with the U.S. Department of Energy. The rocks penetrated by the well to a total depth of 1,219 m were volcanic tuffs of Tertiary age. Hydraulic coefficients calculated from pumping test data indicate that transmissivity ranged from 200 to 790 sq m/day. A radioactive tracer, borehole flow survey indicated that the two most productive zones during this borehole flow survey occurred in the upper part of the Bullfrog Member of the Crater Flat Tuff, depth interval from 721 to 731.5m, and in the underlying part of the Tram Member, depth interval from 864 to 920m. The water is predominantly a sodium biocarbonate type with small concentrations of calcium, magnesium, and sulfate. The apparent age of this composite water sample was determined by carbon-14 date of 17,200 years before present. (USGS)

Water-Resources Investigations Report↗
USGS1984

Geohydrologic and drill-hole data for test well USW H-3, Yucca Mountain, Nye County, Nevada

Test well USW H-3 is one of a series of test wells drilled in and near the southwestern part of the Nevada Test Site for hydraulic testing, hydrologic monitoring, and geophysical logging. The work was performed in cooperation with the U.S. Department of Energy as part of the Nevada Nuclear Waste Storage investigations. The well penetrated volcanic tuffs of Tertiary age to a depth of 1,219 meters. This report presents data collected to determine the hydraulic characteristics of rocks penetrated. Data on drilling operations, lithology, borehole geophysics, hydrologic monitoring, pumping, swabbing, and injection tests for the well are contained in this report. (USGS)

Open-File Report↗
USGS1984

Geohydrologic and drill-hole data for test well USW H-4, Yucca Mountain, Nye County, Nevada

Data are presented on drilling operations, lithology, geophysical well logs, sidewall-core samples, water-level monitoring, pumping tests, injection tests, radioactive-tracer borehole flow survey, and water chemistry for test well USW H-4. The well is one of a series of test wells drilled in the southwestern part of the Nevada Test Site, Nye County, Nevada, in cooperation with the U.S. Department of Energy. These test wells are part of the Nevada Nuclear Waste Storage Investigations to identify sites for storage of high-level radioactive wastes. Test well USW H-4 was drilled in ash-flow tuff to a total depth of 1,219 meters. Depth to water below land surface was 519 meters or at an altitude of 730 meters above sea level. After test pumping at a rate of 17.4 liters per second for approximately 9 days, the drawdown was 4.85 meters. A radioactive borehole-flow survey indicated that the Bullfrog Member was the most productive geologic unit, producing 36.5 percent of the water in the well. The second most productive geologic unit was the Tram Member, which produced 32 percent of the water. The water in test well USW H-4 is predominantly a soft, sodium bicarbonate type of water typical of water produced in tuffaceous rocks in southern Nevada. (USGS)

Open-File Report↗
USGS1983

Geohydrologic and drill-hole data for test well USW H-1, adjacent to Nevada Test Site, Nye County, Nevada

This report presents data collected to determine the hydraulic characteristics of rocks penetrated in test well USW H-1. The well is one of a series of test wells drilled in and near the southwestern part of the Nevada Test Site, Nye County, Nevada, in a program conducted on behalf of the U.S. Department of Energy. These investigations are part of the Nevada Nuclear Waste Storage Investigations to identify suitable sites for storage of high-level radioactive wastes. Data on drilling operations, lithology, borehole geophysics, hydrologic monitoring, core analysis, ground-water chemistry and pumping and injection tests for well USW H-1 are contained in this report.

Open-File Report↗
USGS1983

Water table in rocks of Cenozoic and Paleozoic age, 1980, Yucca Flat, Nevada Test Site, Nevada

The water table at Yucca Flat, Nevada Test Site, Nevada, occurs in rocks of Paleozoic age and in tuffs and alluvium of Cenozoic age and ranges in altitude from about 2,425 feet to about 3,500 feet. The configuration of the water table is depicted by contours with intervals of 25 to 500 feet. Control for the map consists of water-level information from 61 drill holes, whose locations and age of geologic units penetrated are shown by symbols on the map. (USGS)

Water-Resources Investigations Report↗
USGS1982

Results of hydraulic tests in U.S. Department of Energy's wells DOE-4, 5, 6, 7, 8, and 9, Salt Valley, Grand County, Utah

Six exploratory wells were drilled into the cap rock underlying Salt Valley, Utah, for geologic, geophysical, and hydrologic data to augment information obtained from three previous test wells. Drilling of three other test holes was abandoned due to caving and loss of drilling tools, Before reaching the zone of saturation; the upper 100 meters of cap rock is unsaturated. Within the saturated part of the cap rock, hydraulic heads generally decrease with depth and to the northwest in this part of the valley. Hydraulic conductivity of the cap rock, as determined from pumping tests, ranged from 9.3 X 10 -5 to 2.06 X 10 -1 meters per day; as a result, groundwater flow rates in the cap rock are low. Water ranges from a calcium bicarbonate sulfate type on the western edge of the valley to a calcium magnesium sodium bicarbonate, sulfate, chloride type near the center of the valley. Carbon-14 specific activity for cap-rock water yielded an uncorrected age of about 17,000 to 26,000 years before present near the western edge of the valley and about 41,000 years before present near the center of the valley.

Utah↗
USGS1976

Radiochemical monitoring of water after the Cannikin event, Amchitka Island, Alaska, August 1974 and chemical monitoring from July 1972 to June 1974

Radiochemical data from the Arnchitka Island study area were obtained from water samples collected by the U.S. Geological Survey during August 1974. Tritium determinations were made on 18 samples, and gross alpha and gross beta/ gamma determinations were made on 12 samples. No appreciable differences were found between the data obtained during August 1974 and the data obtained before the Cannikin event. Chemical analyses were made on 4 samples collected in 1971, on 15 samples in 1972, on 11 samples in 1973, and 7 samples in 1974. Comparison of these analyses to analyses of samples collected before the Cannikin event indicates no changes outside of the seasonal range normally found at the sampling locations.

Alaska↗
USGS1976

Radiochemical monitoring of water after the Cannikin event, Amchitka Island, Alaska, May 1974

During May 1974, the U.S. Geological Survey collected water samples from Amchitka Island, Alaska. Tritium determinations were made on 99 water samples, and dissolved gross alpha and gross beta/gamma determinations were made on 34 water samples, No appreciable differences were found between the data obtained in May 1974 and the data obtained before the Cannikin nuclear explosion.

Alaska↗
USGS1974

Geologic and hydrologic considerations for various concepts of high-level radioactive waste disposal in conterminous United States

The purpose of this investigation is to evaluate and identify which geohydrologic environments in conterminous United States are best suited for various concepts or methods of underground disposal of high-level radioactive wastes and to establish geologic and hydrologic criteria that are pertinent to high-level waste disposal. The unproven methods of disposal include (1) a very deep drill hole (30,000-50,000 ft or 9,140-15,240 m), (2) a matrix of (an array of multiple) drill holes (1,000-20,000 ft or 305-6,100 m), (3) a mined chamber (1,000-10,000 ft or 305-3,050 m), (4) a cavity with separate manmade structures (1,000-10,000 ft or 305-3,050 m), and (5) an exploded cavity (2,000-20,000 ft or 610-6,100 m) o The geohydrologic investigation is made on the presumption that the concepts or methods of disposal are technically feasible. Field and laboratory experiments in the future may demonstrate whether or not any of the methods are practical and safe. All the conclusions drawn are tentative pending experimental confirmation. The investigation focuses principally on the geohydrologic possibilities of several methods of disposal in rocks other than salt. Disposal in mined chambers in salt is currently under field investigation, and this disposal method has been intensely investigated and evaluated by various workers under the sponsorship of the Atomic Energy Commission. Of the various geohydrologic factors that must be considered in the selection of optimum waste-disposal sites, the most important is hydrologic isolation to assure that the wastes will be safely contained within a small radius of the emplacement zone. To achieve this degree of hydrologic isolation, the host rock for the wastes must have very low permeability and the site must be virtually free of faults. In addition, the locality should be in (1) an area of low seismic risk where the possibility of large earthquakes rupturing the emplacement zone is very low, (2) where the possibility- of flooding by rise is very low, (3) where a possible return of glacial or pluvial climate will not cause potentially hazardous changes in surface- or ground-water regimens, and (4) where danger of exhumation by erosion is nil. The geographic location for an optimum site is one that is far removed from major drainages, lakes, and oceans, where population density is low, and where the topographic relief is gentle in order to avoid steep surface-water drainage gradients that would allow rapid distribution of contaminants in case of accident. The most suitable medium for the unproven deep drill-hole, matrix-holes, and exploded-cavity methods appears to be crystalline rocks, either intrusive igneous or metamorphic because of their potentially low permeabilities and high mechanical strengths. Salt (either in thick beds or stable domes), tuff, and possibly shale appear to be suitable for mined chambers and cavities with separate manmade structures. Salt appears to be suitable because of its very low permeability, high thermal conductivity, and natural plasticity. Tuff and shale appear suitable because of their very low permeabilities and high ion-exchange capacities. Sedimentary rocks other than shale and volcanic rocks, exclusive of tuff, are considered to be generally unsuitable for waste emplacement because of their potentially high permeabilities. Areas that appear to satisfy most geohydrologic requirements for the deep drill hole and the matrix holes include principally (1) the stable continental interior where the sedimentary cover is thin or absent, (2) the shield area of the North-Central States, and (3) the metamorphic belt of Eastern United States--primarily the Piedmont. These areas are possibly suitable also for the exploded cavity and the mined chamber because the possibility of finding rock with very- permeability at depths from 1,000? feet (305? m) to 20,000 feet (6,100 m) appears to be high. The Basin and Range province of Western United States, particula

Open-File Report↗